DIY Powerbank 40.000mAh 18650 QC4.0 Dual USB 5V 4.5A 22.5W

A case for a power bank control board that fits 17x 18650 cells. 

You will need these parts:

1x power bank control board - you can buy it on Aliexpress

The module is great, with 2 USB outputs, 1x USB-C input/output with fast charging, 1x Micro-USB input, and 1x Lightning input. The module supports passthrough (ports can be used while charging) The state of the battery is shown via 4 LEDs. I made a clear-plastic part for light, but those are not finished yet. 

6x M2 square nut

You need to stop the print when you reach the last layer before closing the nut space. Insert the nuts and continue the print.

6x M2x25 screw (HEX or Cheese Head)

17x 18650 cells

The cells are connected in parallel, the total capacity of my cells is about 40Ah, but you can use any cells you like. You need to adjust the resistor on the board according to your cells total capacity. See the listing page for more details.